Timing devices



March 11, 1958 H. L. CLARK 2,826,651

TIMING DEVICES Filed Oct.'4, 1956 4 Sheets-Sheet 1 o l o IE I III, 80

/ 23 INVENTOR.

44 HARaLn 1.. 044px his rranwzys March 11, 1958 H. L. CLARK 2,826,651

' TIMING DEVICES Filed Oct. 4, 1956 4 Sheets-Sheet 2 x Q 1 1/1111 r I f.a

- INVENTOR. HAROLD L. CLARK fi 7 BY JMM his ATTORNEYS March 11, 1958 H.L. CLARK 2,826,651

TIMING DEVICES Filed Oct. 4, 1956 4 Sheets-Sheet 3 I40 22 l K l r/6Or142 INVENTOR. HAROLD L. CLARK 1 ATTORNE y:

. March 11, 1958 H. L. CLARK v TIMING DEVICES Filed Oct. 4. 1956 4Sheets-Sheet 4 fi ATTORNEYS United States Patent'fiice TIMING DEVICESHarold L. Clark, Plantsville, Conn., 'assignor to The Sessions ClockCompany, Forestville, Conn., a corporation of Connecticut ApplicationOctober 4, 1956, Serial No. 613,946

Claims. (Cl. 200-39) This invention relates to timing and timing devicesand especially to settable time-responsive mechanism for operatingelectric switches at predetermined times.

It is, of course, well known to operate switches for controllingelectric circuits by time-responsive mechanism and a variety of forms ofequipment have been devised for this purpose including elements readilyand conveniently settable to a predetermined time at which time thecircuits are automatically opened or closed. In some instances there area plurality of settable controls so that it is possible to preset a timefor circuit closing and then a later time for circuit opening or viceversa. Control of electric appliances such as radios, cooking equipmentand the like can thus be rendered extremely convenient.

Heretofore timing devices which could satisfactorily operate electricswitch means, and especially those capable of several sequentialswitching operations have involved mechanical complexity, the use ofseveral sets of switch contacts, or other features, deemed at the timeindispensable, which made the cost excessive and consequently barred orat least hindered their use for many purposes for which they wouldotherwise be found extremely convenient.

It is an object of the present invention to provide a timing device madeup of few parts which can be produced in inexpensive fashion and whichcan be used to perform the same functions as devices much more complexand expensive in nature.

In particular it is an object of the invention to provide a timingmechanism requiring only a single electric switch for its operation andincluding simplified interconnections for turning the switch on or oifat preset times.

A feature of the invention is the use of a contact assembly or switchwhose contacts are continuously biased to oneposition, together with anoperating lever therefor biased strongly enough to overcome the switchbias and to operate the switch, and time-responsive mechanism forcontrolling the movement of the lever in cooperation with its biasingmeans.

Another feature of the present invention is the operation of a singleone-way-biased, circuit-controlling contact assembly by twotime-responsive systems each having associated means including a biasedlever affecting the contact assembly. One system serves to control theopening of the contacts and the other the closing.

It is also a feature of the invention to provide an arrangement inaccordance with the immediately foregoing feature but in which thecontact opening system also includes means for manually initiallyclosing the contacts when the time for delayed opening is preset if noclosing time is preset, thus avoiding the necessity for a separatecontact closing operation which might be overlooked when used withequipment which does not provide an instantaneous obvious notificationof the closed or open condition of the contacts.

Still another feature of the present invention is the operation of acontact assembly by a biased time controlled lever whose operation maybe controlled either 2,826,651 Patented Mar. 11, 1958.

directly from one settable time-responsive means or through anintermediate control element from a second time-responsive means.

A further feature of the invention is the provision of timing mechanismprovided with on and off time setting assemblies each including a pushbutton which may be pushed and rotated to preset the time period whereinthe push buttons also constitute the sole means for operating thecontact assembly manually to the on and off condition when no timeperiod is present, i. e., when the indicator is set for present time orhas a reading equal to the clock reading.

The present invention is an improvement on the device illustrated in theapplication of Fox and Clark, Serial No. 526,348, filed August 4, 1955,and has for another object the simplification of the control mechanismof said device.

Other objects, features and advantages will become apparent as thedescription proceeds.

In the drawings,

Fig. l is a front elevation of a timing mechanism according to thepresent invention;

Fig. 2 is an end elevation of the device looking from the right towardsthe left in Fig. 1, but with certain of the conventional clock motorgearing omitted for purposes of clarity;

-Fig. 3 is a section taken on line 33 of Fig. 2;

Fig. 4 is a section taken on line 44 of Fig. 3;

. Fig. 5 is a plan of the device of the invention as seen from thebottom in Fig. 10 but with certain parts of the mechanism shown indifferent position from that of Fig. 1;

Fig. 6 is a detail section on an enlarged scale taken substantiallyalong line 66 of Fig. 3, with the parts in the Fig. 5 position;

. Fig. 7 is a section similar to Fig. 6 but showing the parts in theposition they would occupy in accordance with the showing in Fig. l;

, Fig. 8 is a fragmentary perspective of the switch levers and controlmeans illustrating the parts in off position, looking in a directionsubstantially opposite to that of Fig. 5;

Fig. 9 is a perspective view of the leaf spring control element of theinvention;

Fig. 10 is a fragmentary detail elevation of the switch, levers andcontrol means with the parts in the position shown in Fig. 8;

Fig. 11 is a fragmentary view, similar to Fig. 10, but in section alongline 11--11 in Fig. 5, certain of the parts in the foreground beingshown in phantom; and

Figs. 12, 13 and 14 are views similar to Fig. 10, but illustrating theparts in various positions, certain of the parts in the foreground againbeing shown in phantom.

Referring now to the drawings and particularly to Figs. 1 to 5, thetiming mechanism of the present invention is illustrated as including aframe consisting of a front plate 20 and rear plate 22 and suitablespacing posts 23. Mounted on the rear plate 22 is a synchronous motor 24of conventional construction for driving the timing mechanism. Aconventional clock driving train (not shown) is provided for driving aminute shaft 34 and an hour sleeve 28 from the synchronous motor 24 in amanner well known to the art. In Fig. 3 is illustrated in broken lines agear 26, in this case the hour gear of the timing train, connected toand driven by the hour sleeve 28 to which is also connected an hour hand30. The latter runs adjacent a clock dial 32 (see Fig. l). The hour gearand sleeve 26, 28 are supported by a minute sleeve or shaft 34 whichcarries at its end a minute hand 36 operating adjacent the same clockdial 32. The dial 32 is shown as carried by an escutcheon plate 38supported by the front plate 20 of the frame. For convenience in settingthe clock hands 30, 36, an extension 40 and a finger knob 42 may beprovided on the minute shaft 34. Aflixed to the frame at a suitablelocation, for example against the rear surface of the front plate 20, isa contact assembly or switch 44. The switch 44 is a snap switch and isshown as including an actuator 46 which is biased to extended position,and soldering lugs 44a. The extended position of the actuator 46, itwill be understood, may be either an open or closed position of thecontacts in the switch 44, but for the purposes of this description itwill be assumed that the extended position of actuator 46 is associatedwith an open switch or off condition, and that when the actuator 46 ispressed and held in against its biasing force the switch contacts willbe closed or in on position. Movement of the actuator 46 in eitherdirection is termed actuation thereof, while the position away fromwhich it is normally biased will be considered hereinafter as being theoperated position,

Proceeding now to the means for controlling the action of the switch 44,the gear 26 is shown as driving idlers 48 and 48a which drive timinggears 50and 50a respectively. For this purpose, the gear 26 may be thegear which drives the hour sleeve 28 or any other suitable gear in themechanism which rotates at a convenient rate, for example, once in everytwelve hours. The ratios of the gear teeth in gear 26 and gears 50, 50aare preferably such that the gears 50, 5011 will make one revolutionevery 24 hours. Mounted adjacenteach of the gears 50, 50a are timesetting wheels 52, 52a respectively. Inasmuch as the time-responsivemeans or assemblies at either end of the frame are very similar instructure,. the description herein will proceed on the basis of thedetailed features of one only of the assemblies with the understandingthat in the absence of any distinctions made herein the parts of theother assembly are the same as the one described. For purposes ofconvenience the time-responsive assembly at the right hand end of theframe in Figs. 3 and will be desig nated the on assembly 47 and that atthe left hand end the off assembly 47a. The description will proceedprimarily on the basisof a detailed description of the on assembly 47,the corresponding parts of the off assembly being designated by the samereference numerals with the postscript a attached.

Timing gear 50 and time setting wheel 52 are provided with axiallyengageable and disengageable clutch means, for example the lugs 54 andthe matching openings 56, as seen more clearly in Figs. 6 and 7. While asingle lug and socket or opening would provide an operative structure,the reasons for the use of a plurality of each are presented in theaforesaid copending application. The timing gear 50 is shown as integralwith the sleeve 58 and is rotatably mounted on a time setting shaft 60.The gear 50 and shaft 60 are also relatively slidable to a limitedextent. Atfixed to the shaft 60 is an abutment washer 61 by which thegear 50 can be axially moved away from wheel 52 when the shaft 60 ispushed inwardly. The time setting wheel 52, however, has a free slidingnoncircular driving connection with the shaft as indicated by referencecharacter 62 so as to be slidable relative thereto but constrained torotate therewith at all times. A central hub 64 of the wheel 52 extendsthrough and is rotatable in an opening 66 in the front plate 20. Hub 64has a bearing fit in opening 66 and shaft 60 has a rotatable andslidable bearing fit in a suitable opening 67 in the rear plate 22.These two bearing arrangements serve as the mounting for the timeresponsive assembly 47 on the frame of the timer. The general axialposition of the assembly is determined essentially by the location ofthe hub 64 which is held in position in the'opening 66 by a suitableretainer flange 68. A compression spring 70 surrounds the sleeve 58andabuts against the back plate 22 so as to urge the gear 50 towards thesetting wheel 52 at all times, and to urge the lugs 54 into the openings56 whenings 56. The degree of inward travel of shaft substituted forthis arrangement.

openings 56 from registry with the lugs 54 so that the gear 50 andwheel'52 will remain axially separated until" the timing gear has beenrotated by gear 48 throug'han angle sufficient to restore registry oflugs 54 and open- 60 may be determined in any suitable manner. Forinstance, the engagement of a conical portion 186 of the shaft 60 in aconical stop recess 167 in hub 64 may serve this purpose. The range ofdisplacement of gear 50 and the thickness of its driving gear 48 aresuch that their meshed relationship is maintained at all times as can beseen from Figs. 6 and 7. The time setting wheel conveniently carries adial 76 having time indicia 78 (Fig. 1) which will normally be visiblethrough a suitable opening '80 in escutcheon plate 38, to indicate thetime of day at which the axial motion of gear 50, occasioned by theentrance of lugs 54 into openings 56, will occur.

It will be noted that the time setting wheel 52 has on its face adjacentplate 20, a peripheral frictional bearing element 82 which rides againstfront plate 20 under a gear 50.

The axial motion of gear 50'is arranged to generate the displacementrequired to actuate switch 44, and the displacement is transmitted tothe switch by an on actuating member or lever which combines with thetime-responsive assembly 47 to form an on timing means for the switch44. The lever 100 has an opening 102 (see Fig. 3) at an intermediatepoint in its length loosely receiving the sleeve 58 with the leverarranged between gear 50 and the end of spring 70. Preferably dimples orother rounded-local projections 104 are formed on lever 100 to provide amember suitably localizing its bearing against gear 50 for easy rockingmotion. One end of the lever has a free rocking connection with theplate 20, and the other end108 is positioned totravel in a path where itwill strike the actuator 46 of switch 44. The free rocking. connectiontakes the form of a. bent-up, notched tongue 106 at the end of lever100, loosely engaged in a T-slot 107 in plate 20, as best seen in Fig.4, although any suitable pivotal mounting may be Thus it can be seenthat when the end 108 of the lever 100 moves towards front plate 20 dueto the action of spring 70,. actuator 46 is operated or depressed toclose switch 44. When, however, the'gear 50 of timing assembly 47 movesthe lever 100 and its end 108. away from front plate 20, to set positionas in Fig. 7, the actuator 46 is released and allowed to return tonormal switch open position.

With particular reference to Figs. 8 and 9, there is also provided acontrol-means whose action cooperates with that of thespring 58 and gear50 in controlling the positioning of end 108 of lever 100. The controlmeans or member 120 comprises an arm which in the specific embodimenthere shown takes the form of a leaf spring 122 mounted on the frontplate 20 and projecting rearwar-dly adjacent the end 108 of lever 100.One convenient method for mounting the same is to'provide a bent tab 124having an opening 126 which may be used to hold the control means 120 byclamping the tab between the switch 44 and the front plate 20 andpassing one of the mounting fasteners for the switch through saidopening 126. The upper end' of the leaf spring is normally biased to theright, as viewed in Fig. 10, and carries an operating member 128 forcooperation with the lever 100 in a manner which will presently appear.The operating member 128 is preferably formed as a tab integral with andmerely bent from the material of the leaf spring 122, and is given aV-s'hape to provide oppositely sloping cam surfaces 130 and 132. Forcooperation with the leaf spring, the free end 108 of lever 100 is bentup from the plane of the lever to form a cam portion 134 extending inthe direction of pivotal movement. This cam portion or tongue is formedto provide a V-notch in the edge adjacent spring 122. This notchprovides oppositely sloping cam surfaces 136 and 138 for cooperationwith the cam surface of the operating member 128. The operating member128 has two positions one being its innermost or preventing or blockingposition under the infiuence of leaf spring 122; the other being itsouter nonblocking or on-permitting position when the leaf spring isdeflected outwardly as will be described presently. Normally when themember 128 is urged inwardly to blocking position by the leaf spring122, its cam surface 130 reacts against cam surface 136 of tongue 134and cams the same in a direction such that lever end 108 is withdrawnfrom and held away from switch 44, and the switch operator 46 ispermitted to move to its off position as seen in Figs. 8 and 10. Theleaf spring 122 has sufficient force to accomplish this even against theeffect of spring 70 due to the leverage arrangement. Thus the operatingmember 128 has the primary function of blocking the on movement of lever100, or of moving it to 01f position when it is on.

Whenever the lever 100 is forced away from front plate 20 as by gear 50(see Fig. 12), the cam surface 138 ofits tongue 134 reacts against camsurface 132 on operating member 128 and earns the leaf spring tononblocking position. The control means 120 thereupon becomes latched inthis position in a manner to be hereinafter described, and, if nototherwise prevented, the end 108 of lever 100 will move under influenceof the spring 70 to the Fig. 12 position, wherein the switch actuator 46has been moved by the lever end 108 to on position.

It will be noted that the tongue 134 has a guide edge 140 designed torun against a fixed guiding surface, furnished for example by a tab 142bent inwardly from the rear plate 22. This arrangement supports thelever end against the side thrust of leaf spring 122 and guides thelever for free oscillating movement about its rockable :mounting 106,107.

In order to operate the switch 44 from the time-responrsive assembly 47a(which is substantially identical with assembly 47 as explainedheretofore), ,an off actuatzing member or lever 150 is provided whichcombines with .the time-responsive assembly 47aand the control means.120 to provide an ofi timing means. The lever 150 .has an opening 152at an intermediate point in its length .loosely receiving the sleeve 58awith the lever arranged between gear 50a and the end of spring 70a. Thelever 150 is also preferably provided with dimples or round localprojections 154 similar to projections 104 on lever' 100 and for thesame purpose. One end of the lever has a free rocking connection onplate 20 and the other end 158 is positioned adjacent the control means120 .and is provided with a bent-up tongue or cam portion 160 forinteraction with an operating latch member 162 taking the form of a tabon leaf spring 122. Tongue 160 is thus disposed in juxtaposition to camportion 134 of lever 100 and extends parallel thereto. The free rockingconnection of lever 150 on plate 20 is the same as that of itscounterpart, lever 100. As in the case of lever 100 also, the tongue 160of lever 150 has a guide edge 164 which bears against the surface ofguide tab 142 on rear plate 22 under the urging of leaf spring 122.

Tongue 160 of lever 150 has a notch in its edge adjacent the latchmember or tab 162 of leaf spring 122. The lower portion of this notch,as seen in Fig. 10, slopes inwardly to provide a cam surface 166corresponding generally with adapted to interact with an extension ofsurface 132 on leaf spring 122. The'upper edge of the notch in tongue160 is substantially perpendicular to the left hand edge of the tongueand provides a latching abutment 168 against which the tab 162 of leafspring 122 may engage.

One function of the 011' lever 150, therefore, as seen in Fig. 10, is tolatch the control means in a condition preventing lever from actuatingswitch 44 to on position. This is done by allowing the operating member128 of leaf spring 122 to move, under the urging of the leaf spring,into the V-notch in tab 134. In this condition, the operating end 108 oflever 100 is held out of operating engagement with plunger 46 of theswitch. If, however, the lever is raised against the force of spring 70aby gear 50a, thereby at the same time camming leaf spring 122 to theleft as seen in Fig. 12 by interaction of cam surfaces 132, 166 of theleaf spring and tongue 160, respectively, lever 100 is free to movetoward switch 44 and actuate plunger 46 to its operated position. Thismovementis provided by spring 70 acting against lever 100.

Another function of the lever 150 is to latch the leaf spring 122 in theposition shown in Fig. 13 so that lever 100 is free to operate theswitch. This condition is brought about by raising lever 100 so thatinteraction between surfaces 132, 138 of the leaf spring and tongue-134, respectively, earns the spring sufficiently to the left (as viewedin Fig. 13) to disengage latching tab 162 from latching abutment 168,allowing lever 150 to move toward front plate 20, under the urging ofspring 70a, until tab 162 rests on the outer edge 170 of abutment 168.Upon the return of lever 100 towards front plate 20, the operatingmember 128 of leaf spring 122 can no longer engage the notch in tongue134, and the on lever 100 therefore is free to travel to a position inwhich switch 44 is actuated to on condition. This condition isillustrated in Fig. 14.

From the foregoing description it will be plain that the control means120 has two positions, namely (1) an off position (to which it isnormally biased by its own resilience) in which it prevents operation ofthe switch actuator 46 and (2) an on permitting position (in which itmay be latched on either side of the notch in tongue by latch element162) in which such prevention is removed and the on or off condition ofthe switch actuator 46 is determinable by the position of gear 50through lever 100. The several ways in which the timer device can beoperated, whereby to bring about the various conditions just mentioned,will now be described.

Automatic operation In order to preset a time for a turning on operationof the switch 44, the operator will push the on" knob 74 to disengagelugs 54 from openings 56, and rotate the knob to remove the lugs 54 fromalignment with openings 56, whereby the gear 50 and wheel 52 aremaintained in spaced relationship and the lever 100 is held in offposition until the timing train returns the lugs 54 and openings 56 toregistering position. The setting rotation of the knob by the operatoris, of course, continued until there appears in opening 78 the clocktime at which it is desired to have switch 44 close. The pushing in ofthe knob 74 causes the latching tab 162 to latch the control means 120in on permitting position and, together with the rotation of the knob,places the parts generally in the position of Figs. 7 and 14 (exceptthat in Fig. 14 the lever 100 would be raised instead of lowered asshown, and switch actuator 46 would consequently be in off positionuntil the preset time period has elapsed and lugs 54 are realigned withholes 56). If no particular predetermined off time is required, theparts will remain in the cam surface 138 of tongue 134 and the statedposition until 7' the preset on time lugs 54 will drop to operate theactuator 46 and close the switch, which will then remain closedindefinitely.

'if it is also desired to preset a time for subsequently opening switch44, the operator, in addition to the above described operation, willalso push the off knob or manually accessible operator 74a to disengagethe corresponding lugs and openings (not shown) of the timeresponsiveassembly 47a; He will then rotate the knob until'there appears inopening 78a the clock time at which it is desired to have switch 44 openagain. Then the time will run as aforesaid until the predeterminedclosing of the switch 44 has occurred, whereupon the parts will appearas shown in Fig. 12. The time will continue to run until the lugs andopenings of the timeresponsive assembly 47a are in register, when thelugs will drop into the openings permitting lever 150 to lower until tab162 drops into the notch in tongue 160 and is engaged against abutment168. In the course of this action, cam surface 136) on the leaf springacts against cooperating surface 136 on tongue 134, raising the end 108of arm 100 to lift it away from actuator 46 and open the switch as seenin Fig. 10.

' In some instances it may be desired to close the switch immediately,and merely arrange "for a preset time for the switch to openautomatically.- In this situation, there is no need to perform anyoperation with the on button to close the switch, for the cam portion166 of tongue 160 will perform this function when the button 74a ispushed to make the off time setting as previously described.

From the foregoing it will be appreciated that a very convenientarrangement is provided for making time settings for individualautomatic on or off operations, when either one is desired without theother. Each of the knobs 74, 74a will set its own initial switchcondition under such circumstances, provided only that the other knob isarranged for no preset time interval.

The reason for this will be apparent when it is noted that each shaft'60 or 60a normally brings about a different switch condition at theopposite ends of its reciprocatory travel. In other words the on shaft60, when extended, produces an on condition of the switch 44, and whenpushed in produces an off condition of the switch (i. e. a conditionopposite to its own designation). Likewise the off shaft 60a, whenextended, produces normally an off condition of switch 44 as in Fig. 10,but when pushed inwardly it normally produces an on condition of theswitch as condition opposite to the shaft designation). Thus eachcontrol incorporates the essential features for an individual settingand avoids the necessity for the extra step of somehow turning theswitch to the preliminary on or off condition in connection with thepresetting of an off or on automatically timed switch operation. It isthus very unlikely that the initial switch condition will be overlooked,as would be possible with prior timers where the circuit included a slowacting device which did not at once attract attention to its condition,e. g. an electric heating element or a radiation receiving set whoseelements have a warm-up period before an audible or visible signal isexperienced by the operator.

Manual operation When the operator desires merely to operate the deviceto presently open or close the switch without any intervening presettime interval, he can accomplish the same in a very simple anduncomplicated fashion with the device of this invention. Assuming thatno preset time period is running, of course, and that the lugs '54 arein openings 56 (and the corresponding lugs andopening of assembly 47aare in mesh), all that is required ,is for the operator to push and thenrelease the knob bearing the designation corresponding to the type ofswitch actuation desired. Thus, if he pushes the on button 74, lever hasbeen reached, whereupon the i into openings 56, permitting lever 1'00 inFig. 12 (again a ways than thosejhere'in set 190 wilibe raised and leafswitch 122; carnrnedto release tab 1'62'from beneath abutment 168 to theposition shown in'Fig. 13,1atclring-the control means 120 in thatposition so that it cannot interfere with tongue 134. Then when pressureon knob 74 is relaxed, the lugs 54 re-enter the openings 56 allowinglever 109 to lower so that its end strikes actuator 46 closing theswitch and holding it closed as shown in Fig. 14. If the operator pushesthe oknob 74a he raises lever 150, releases the control means 120fromthe Fig. 14 positionand allows it to move to the Fig. 10positiomcausing the leaf spring to cam lever 100 upwardly and releasethe actuator 46. This operation can take place withoutufully disengagingthe lugs from the respective openings in the time-responsive assembly47a. w

It can be seen from 't-he immediately foregoing description that theproblem of selecting between automatic and manual operation is made easyof solution for the operator, for the same control elements, 74a, areused in :a simple fashion in either case, and no conversion setting of aseparate element to condition the mechanism for one type of operation orthe other is required. This simplicity of operation is also achieved,furthermore, without rendering the mechanism more complex, and in "factsimplifying it in many respects as compared with other timers ofgenerally analogous function. If an automatic time setting is in ellectand it is desired to render the same 'nugatory and to change to manualoperation, it is necessary only to rotate'the knobs 74, 74a, until thelugs of the timing assemblies 47, 47a, are in each case received in thecorresponding openings, whereupon the-device is ready for manualoperation.

So that it will be possible for the operator to tell at aglance whether1 a-time periodhas'beenset or-( 2) the device is in condition for manualoperation, mechanism may be provided for closing the windows 30 or -toobscure the dial '76 or 76a whenever the corresponding knob '74 or 74ahas no timesetting and is free for manual operation. This mechanism isthe same as that described in the aforesaid -co-pending applicationc'f Fox and Clark, Ser. No. 526,348, to which reference is made for adetailed description of :the construction and operation of thatmechanism.

The invention :may be carried out in other specific forth Withoutdeparting from the spirit and essential characteristics of theinvention, and the present embodiment is, therefore, to be considered inall respects as illustrative and not restrictive, and 'allichangescomingwithin the meaning and equivalency range of the appended claims areintended to be embraced therein.

What is claimed is:

7 .1. In a timer device for .an electrical appliance, a frame'lmember, aswitch mounted on said frame member and having :a contact assemblyoperable between open and .closed circuit positions and normally biasedto one of said positions; actuating means for said switch comprisinga-:lever;pivotally supported on said frame member and .normally biased-;to ;overcome the bias .of said contact assembly and move it :to anoperated position, said lever being formed at a free end to provide acam portion extending inthe direction of pivotal movement; a clockmechanism; settable time-responsive means driven by.said.clock mechanismand engagea'ble with said lever for overcoming .its bias and :holdingthe lever in nonoperating position until a'pre-set time periodhasexpired; control -means independent-of said time-responsive -means forcontrolling the position of said lever, said control means comprising anarm resiliently mounted on said frame and having a "free end projectinginto engagement with the free end ofsaid lever, said arm being movablebetween a blocking position, in .whichit engages the cam portion ofsaid'lever and prevents movement of said contact assembly to operatedposition by said lever, and a nonblocking position, said arm beingnormally biased to namely knobs 74,

blocking position; and latch means for latching said arm in nonblockingposition.

2. A timer device as defined in claim 1, wherein the cam pOrtion of saidlever has a cam surface, and said arm has a complementary cam surface,which surfaces engage upon moving said lever manually against its biasto move said arm to, and latch it in, said nonblocking position.

3. A timer device as defined in claim 2, wherein the cam portion of saidlever is provided by a V-notch formed m said le/er and saidcomplementary cam surface on said arm is formed by a V-shaped operatingmember on the latter.

4. in a timer device for an electrical appliance, a frame member, aswitch mounted on said member and having a contact assembly operablebetween open and closed circuit positions and normally biased to one or"said positions; switch actuating means comprising a lever pivotallysecured to said member and biased to overcome the bias of said contactassembly and move it to an operated position; means engageable with saidlever to move it out of its normally biased position comprising a set ofaxially separable, rotatable clutch members having a registeringposition in which they are locked together against relative rotation butwhich are capable of relative rotation when axially separated, saidclutch members in nonregistering positions blocking said lever toprevent its movement of said contact assembly to said operated position;clock mechanism, and means for driving one of said clutch members fromsaid mechanism whereby said one clutch member is rotated relative to theother until registration between them occurs; a control membercomprising a leaf spring biased normally to engage the free end of saidlever and prevent movement of said contact assembly to said operatedposition independently of said clutch members; and means for latchingsaid leaf spring out of blocking position.

5. In a timer device for controlling the operation of an electricalappliance, a switch for opening and closing an electrical circuit andoperable between actuated and unactuated positions, means normallybiasing said switch to its unactuated position, and a plunger for movingsaid switch to its actuated position; a frame on which said switch issupported; control means for actuating said switch including a pair oflevers, each of which is pivotally supported at one of its ends uponsaid frame and has a free end extending into juxtaposition with the freeend of the other, said free ends being formed to extend substantiallyparallel to each other in the direction of pivotal movement of saidlevers; each of said levers in a given direction about its respectivepivot axis, and manually settable time-responsive means for moving eachof said levers in the opposite direction against said resilient means; aclock mechanism for controlling said time-responsive means; a leafspring supported on said frame and having a free end projecting parallelto the adjacent free ends of said levers and in resilient contact withthem; said spring having camming surfaces formed on it and each of saidlever free ends being formed to provide cooperating camming surfacesengaged, respectively, by said spring surfaces; one of said levers beingengageable with said switch plunger and being urged by its resilientmeans to overcome said normal switch bias and move the switch to itsactuated position, said one lever being resiliently restrained againstsuch movement by engagement of the camming surface of its free end withthe cooperating camming surface of said leaf spring; the camming surfaceof said other lever reacting with the respective surface of said spring,when said other lever is moved against its normal bias, to cam saidspring away from said one lever, whereby the latter is freed to contactsaid plunger and move said switch to its actuated position.

resilient means normally urging 6. A timer device as defined in claim 5,wherein said other lever is formed at its free end to provide a latchingabutment and said spring is formed to provide a cooperating tab, saidtab being engageable behind said abutment to prevent full travel of saidother lever toward said given direction.

7. A timer as defined in claim 6, wherein said spring tab is disengagedfrom behind said abutment upon movement of said spring away from itsnormally biased posi tion and said other lever is then freed to travelto the full position in said given direction.

8. A timer device as defined in claim 7, wherein said latching abutmentis formed to provide an outer edge upon which said spring tab is adaptedto rest in the full position of said other lever, whereby said spring islatched in a position permitting said one lever to move said switch toits actuated position.

9. A timer device as defined in claim 6, wherein said cam surface andlatching abutment of said other lever are provided by a notch formed insaid other lever, said timeresponsive means being manually operable todisplace said other lever against said resilient means and settable toretain said other lever in such displaced position for a selected periodof time whereby said spring is latched in a position permitting said onelever to move said switch to its actuated position during such period oftime.

10. In a timer device for an electrical appliance, a frame, a switchcontact assembly on said frame having open and closed circuit positionsand normally biased to one of said positions; means for actuating saidcontact assembly including a first lever pivotally supported on saidframe and normally biased to overcome the bias of said contact assemblyand to move it to an operated position, said lever being formed toprovide a free end having a cam portion extending in the direction ofpivotal movement of said lever; a. second lever pivotally supported onsaid frame and likewise formed to provide a free end having a camportion, said latter portion being in juxtaposition with that of saidfirst lever and generally parallel thereto, said second lever beingnormally biased in the same direction as the first; first and secondsets of timeresponsive means engaging said first and second levers,respectively, each set comprising axially separable clutch members, oneof which engages its respective lever and moves it out of normal biasedposition when said clutch members are axially separated, said membersbeing rotatable relative to each other when axially separated and havingregistering means maintaining axial separation thereof except in apredetermined rotated position; means for manually separating saidclutch members axially and effecting relative rotation between them tomaintain them out of registering position; and clock mechanism drivingone of said members to return it to registering position with the other;detent means comprising an arm resiliently mounted on said frame andhaving a free end projecting into yielding engagement with the camportions of the free ends of said levers and normally blocking saidfirst lever to prevent it from moving said contact assembly to saidoperated position; said cam portion on said second lever being operable,upon actuation of said second lever by separation of its clutch members,to move said arm out of blocking engagement with respect to said firstlever, whereby the latter is freed to move said contact assembly to saidoperated position.

References Cited in the file of this patent UNITED STATES PATENTS1,944,055 Arden Jan. 16, 1934 2,200,110 Andersen May 7, 1940 2,231,603Sprenger Feb. 11, 1941

